Genetic Background and Sex Significantly Influence Bone Response to Osteoporosis Drug PTH
A mouse study published on bioRxiv found that skeletal response to teriparatide (PTH 1-34), a widely used osteoporosis treatment, varies significantly by genetic strain and sex. Researchers treated male and female mice from eight genetically diverse inbred strains for four weeks and measured bone changes using multiple imaging and mechanical methods. The findings suggest that personalized medicine approaches may improve treatment outcomes for osteoporosis patients.
Researchers administered intermittent parathyroid hormone (PTH 1-34, or teriparatide) to male and female mice from eight genetically distinct inbred strains to investigate why clinical response to the anabolic drug varies so widely among patients. After four weeks of treatment, bone phenotypes were assessed via DXA, microCT, and mechanical testing, revealing that response was highly dependent on both genetic background and sex. Some strains responded at the femur but not the spine, and vice versa, mirroring clinical patterns in which hip non-response is more common than spine non-response. Heritability estimates for PTH-induced changes in bone mineral density, cortical area, breaking strength, and trabecular bone volume fraction (BV/TV) ranged from moderate to high, with BV/TV showing the strongest genetic influence. Notably, the mechanism of cortical bone response differed by sex: males showed periosteal expansion while females exhibited endosteal remodeling. The authors argue these results support the use of genetically diverse mouse models to map the genetic architecture of PTH response and call for future genome-wide association studies in outbred mice to identify specific loci involved.
What's missing
As a preprint, this study has not yet undergone peer review. The study is limited to inbred mouse strains, and direct translation to human genetic diversity remains uncertain. The specific genetic loci mediating differential PTH response were not identified in this work. The study does not address dose-response variation or longer treatment durations, and it is unclear whether the sex-specific cortical remodeling mechanisms observed in mice correspond to those seen in male and female osteoporosis patients.
What different sources said
- bioRxivCenter
Bone response to intermittent parathyroid hormone (PTH) is both genetic and sex specific
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